Integrative Biology Journals

Plant Diversity ›› 2025, Vol. 47 ›› Issue (03): 454-465.DOI: 10.1016/j.pld.2024.08.001

• Articles • Previous Articles     Next Articles

Drought tolerance traits explain differential stem growth rates of evergreen and deciduous trees in a tropical karst forest

Yu-Mei Yana,b, Ze-Xin Fanb,c, Pei-Li Fub,c, Zhi-Yong Zhanga   

  1. a. Lushan Botanical Garden, Jiangxi Province and Chinese Academy of Sciences, Lushan 332900, Jiangxi, China;
    b. CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla 666303, Yunnan, China;
    c. Ailaoshan Station of Subtropical Forest Ecosystem Studies, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Jingdong 676209, Yunnan, China
  • Received:2023-10-17 Revised:2024-07-29 Online:2025-05-21 Published:2025-05-25
  • Contact: Ze-Xin Fan,E-mail:fanzexin@xtbg.org.cn
  • Supported by:
    This work was financially funded by the National Natural Science Foundation of China (3186113307, 31770533, 31870591) and the West Light Talent Program of the Chinese Academy of Sciences (xbzg-zdsys-202218).

Drought tolerance traits explain differential stem growth rates of evergreen and deciduous trees in a tropical karst forest

Yu-Mei Yana,b, Ze-Xin Fanb,c, Pei-Li Fub,c, Zhi-Yong Zhanga   

  1. a. Lushan Botanical Garden, Jiangxi Province and Chinese Academy of Sciences, Lushan 332900, Jiangxi, China;
    b. CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla 666303, Yunnan, China;
    c. Ailaoshan Station of Subtropical Forest Ecosystem Studies, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Jingdong 676209, Yunnan, China
  • 通讯作者: Ze-Xin Fan,E-mail:fanzexin@xtbg.org.cn
  • 基金资助:
    This work was financially funded by the National Natural Science Foundation of China (3186113307, 31770533, 31870591) and the West Light Talent Program of the Chinese Academy of Sciences (xbzg-zdsys-202218).

Abstract: The karst forest in southwestern China is characterized by thin soil layers, numerous fissures and holes, resulting in low soil water availability and poor water retention, making it challenging for plant growth and survival. While the relationship between plant functional traits and tree growth performance has been extensively studied, the links between tree seasonal growth and drought-tolerant traits in tree species with different leaf habit remains poorly understood. This study evaluated the associations between four-year averaged rainy season stem diameter growth rate and 17 branch and leaf traits across evergreen and deciduous species in a tropical karst forest in southwest China. The cross-species variations in tree growth rates were related to plant hydraulic traits (e.g., vessel lumen diameter, xylem vessel density, stomatal density, and stomatal size) and leaf anatomical traits (e.g., total leaf thickness, lower/upper epidermis thickness, and spongy thickness). The growth of evergreen trees exhibited lower hydraulic efficiency but greater drought tolerance than deciduous tree, which enabled them to maintain higher persistence under low soil water availability and consequently a relatively longer growing season. In contrast, deciduous species showed no correlation between their functional traits and growth rate. The distinct water use strategies of evergreen and deciduous trees may offer a potential explanation for their co-existence in the tropical karst forests.

Key words: Functional traits, Growth rates, Drought-tolerant, Hydraulic conductivity, Leaf anatomy traits, Tropical karst forest

摘要: The karst forest in southwestern China is characterized by thin soil layers, numerous fissures and holes, resulting in low soil water availability and poor water retention, making it challenging for plant growth and survival. While the relationship between plant functional traits and tree growth performance has been extensively studied, the links between tree seasonal growth and drought-tolerant traits in tree species with different leaf habit remains poorly understood. This study evaluated the associations between four-year averaged rainy season stem diameter growth rate and 17 branch and leaf traits across evergreen and deciduous species in a tropical karst forest in southwest China. The cross-species variations in tree growth rates were related to plant hydraulic traits (e.g., vessel lumen diameter, xylem vessel density, stomatal density, and stomatal size) and leaf anatomical traits (e.g., total leaf thickness, lower/upper epidermis thickness, and spongy thickness). The growth of evergreen trees exhibited lower hydraulic efficiency but greater drought tolerance than deciduous tree, which enabled them to maintain higher persistence under low soil water availability and consequently a relatively longer growing season. In contrast, deciduous species showed no correlation between their functional traits and growth rate. The distinct water use strategies of evergreen and deciduous trees may offer a potential explanation for their co-existence in the tropical karst forests.

关键词: Functional traits, Growth rates, Drought-tolerant, Hydraulic conductivity, Leaf anatomy traits, Tropical karst forest